The rapid development in miniaturized personal wearable devices has significantly stimulated the pursuit for ultrathin, flexible, and lightweight energy storage devices. As one of the most promising power supply devices, supercapacitors have attracted great interest owing to their long operating lifetime, high power density, and fast charge–discharge rate. However, conventional supercapacitors pose challenges when being integrated with miniaturized wearable devices. In this regard, micro-supercapacitors with unique in-plane interdigitated electrode design provide flexibility and ease of integration with wearable and portable electronics. This review discusses the recent progress on fabrication strategies of interdigitated electrode arrays for flexible supercapacitors. Strategies toward their practical applications for powering integrated systems are presented. Finally, the future perspectives of flexible micro-supercapacitor are discussed.